Question 171362
When trying to decide if an ordered pair is a solution of a system of liner equation if the x is already negative and the x value given is also negative would it turn positive or stay negative? 
Ex: (-9,5)
-x + 3y = 24
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Comment: the negative of a negative is a positive.
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Just substitute the values and see if you get a true statement.
-(-9) + 3(5) = 24
9 + 15 = 24
24= 24
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True so (-9,5) is one (of an infinite number) of solutions.
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Cheers,
Stan H.